s3: add comment about what the FSCTL_QUERY_ALLOCATED_RANGES currently does

diff --git a/source3/smbd/nttrans.c b/source3/smbd/nttrans.c
index 46edc066861740863d06199e6156977372be8e09..a03a0b1a55b92b86c004f98205c143d448697717 100644 (file)
--- a/source3/smbd/nttrans.c
+++ b/source3/smbd/nttrans.c
@@ -2217,6 +2217,12 @@ static void call_nt_transact_ioctl(connection_struct *conn,
        }
        case FSCTL_QUERY_ALLOCATED_RANGES:
        {
+               /* FIXME: This is just a dummy reply, telling that all of the
+                * file is allocated. MKS cp needs that.
+                * Adding the real allocated ranges via FIEMAP on Linux
+                * and SEEK_DATA/SEEK_HOLE on Solaris is needed to make
+                * this FSCTL correct for sparse files.
+                */
                NTSTATUS status;
                uint64_t offset, length;